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Text File  |  1996-09-28  |  3KB  |  77 lines
  1.       subroutine passb5 (ido,l1,cc,ch,wa1,wa2,wa3,wa4)
  2.       implicit double precision (a-h,o-z)
  3.       dimension       cc(ido,5,l1)           ,ch(ido,l1,5)           ,
  4.      1                wa1(1)     ,wa2(1)     ,wa3(1)     ,wa4(1)
  5.       data tr11,ti11,tr12,ti12 /.309016994374947,.951056516295154,
  6.      1-.809016994374947,.587785252292473/
  7.       if (ido .ne. 2) go to 102
  8.       do 101 k=1,l1
  9.          ti5 = cc(2,2,k)-cc(2,5,k)
  10.          ti2 = cc(2,2,k)+cc(2,5,k)
  11.          ti4 = cc(2,3,k)-cc(2,4,k)
  12.          ti3 = cc(2,3,k)+cc(2,4,k)
  13.          tr5 = cc(1,2,k)-cc(1,5,k)
  14.          tr2 = cc(1,2,k)+cc(1,5,k)
  15.          tr4 = cc(1,3,k)-cc(1,4,k)
  16.          tr3 = cc(1,3,k)+cc(1,4,k)
  17.          ch(1,k,1) = cc(1,1,k)+tr2+tr3
  18.          ch(2,k,1) = cc(2,1,k)+ti2+ti3
  19.          cr2 = cc(1,1,k)+tr11*tr2+tr12*tr3
  20.          ci2 = cc(2,1,k)+tr11*ti2+tr12*ti3
  21.          cr3 = cc(1,1,k)+tr12*tr2+tr11*tr3
  22.          ci3 = cc(2,1,k)+tr12*ti2+tr11*ti3
  23.          cr5 = ti11*tr5+ti12*tr4
  24.          ci5 = ti11*ti5+ti12*ti4
  25.          cr4 = ti12*tr5-ti11*tr4
  26.          ci4 = ti12*ti5-ti11*ti4
  27.          ch(1,k,2) = cr2-ci5
  28.          ch(1,k,5) = cr2+ci5
  29.          ch(2,k,2) = ci2+cr5
  30.          ch(2,k,3) = ci3+cr4
  31.          ch(1,k,3) = cr3-ci4
  32.          ch(1,k,4) = cr3+ci4
  33.          ch(2,k,4) = ci3-cr4
  34.          ch(2,k,5) = ci2-cr5
  35.   101 continue
  36.       return
  37.   102 do 104 k=1,l1
  38.          do 103 i=2,ido,2
  39.             ti5 = cc(i,2,k)-cc(i,5,k)
  40.             ti2 = cc(i,2,k)+cc(i,5,k)
  41.             ti4 = cc(i,3,k)-cc(i,4,k)
  42.             ti3 = cc(i,3,k)+cc(i,4,k)
  43.             tr5 = cc(i-1,2,k)-cc(i-1,5,k)
  44.             tr2 = cc(i-1,2,k)+cc(i-1,5,k)
  45.             tr4 = cc(i-1,3,k)-cc(i-1,4,k)
  46.             tr3 = cc(i-1,3,k)+cc(i-1,4,k)
  47.             ch(i-1,k,1) = cc(i-1,1,k)+tr2+tr3
  48.             ch(i,k,1) = cc(i,1,k)+ti2+ti3
  49.             cr2 = cc(i-1,1,k)+tr11*tr2+tr12*tr3
  50.             ci2 = cc(i,1,k)+tr11*ti2+tr12*ti3
  51.             cr3 = cc(i-1,1,k)+tr12*tr2+tr11*tr3
  52.             ci3 = cc(i,1,k)+tr12*ti2+tr11*ti3
  53.             cr5 = ti11*tr5+ti12*tr4
  54.             ci5 = ti11*ti5+ti12*ti4
  55.             cr4 = ti12*tr5-ti11*tr4
  56.             ci4 = ti12*ti5-ti11*ti4
  57.             dr3 = cr3-ci4
  58.             dr4 = cr3+ci4
  59.             di3 = ci3+cr4
  60.             di4 = ci3-cr4
  61.             dr5 = cr2+ci5
  62.             dr2 = cr2-ci5
  63.             di5 = ci2-cr5
  64.             di2 = ci2+cr5
  65.             ch(i-1,k,2) = wa1(i-1)*dr2-wa1(i)*di2
  66.             ch(i,k,2) = wa1(i-1)*di2+wa1(i)*dr2
  67.             ch(i-1,k,3) = wa2(i-1)*dr3-wa2(i)*di3
  68.             ch(i,k,3) = wa2(i-1)*di3+wa2(i)*dr3
  69.             ch(i-1,k,4) = wa3(i-1)*dr4-wa3(i)*di4
  70.             ch(i,k,4) = wa3(i-1)*di4+wa3(i)*dr4
  71.             ch(i-1,k,5) = wa4(i-1)*dr5-wa4(i)*di5
  72.             ch(i,k,5) = wa4(i-1)*di5+wa4(i)*dr5
  73.   103    continue
  74.   104 continue
  75.       return
  76.       end
  77.